From our pals at The Infrastructurist, a round-up of some of their best posts this week:

The World's 10 Greatest Urban ParksWe take an aerial tour of the world's most amazing urban green spaces, looking at ten large urban parks situated near the heart of major cities. The shapes range from the "perfect square" geometry of Central Park to giant overflowing Monsanto Forest Park in Lisbon--each one complex and unique.A Gallery Of Abandoned Subway StationsEven healthy, vital metro systems like New York or Paris shutter underused stations from time to time. Then there are small city subways like those in Rochester or Cincinnati that have been shut down entirely. We've put together a photo tour of subway stations that have become modern ruins.

Would $5 Gas Get Commuters To Carpool Or Take Mass Transit?That's exactly what Americans told researchers in a new study about commuting. In fact, an stunning 70 percent of people said that by the time pump prices hit $5, they would be exploring alternatives to driving alone to work each day. One timely idea for reducing driving and congestion? A four-day work week.

Freeway Air Pollution Triggers 'Fight Or Flight' ResponseWe've always know that air pollution isn't good for the human body - but new research is showing just how odd and disturbing the effects can be. It turns out that small particulate pollution, spewed in large quantities by diesel trucks, activates an instinctive fear response in the automatic nervous system, raising blood pressure and the risk of heart attacks--not to mention road rage.

The World's Weirdest SuburbsArtist Ross Racine has imagined an amazing array of suburban housing developments that straddle the line between absurd and totally plausible. A subdivision shaped like a cloud or an ice cream sundae? Just try to tell us no developer has tried to build something like that...

Ha! A Photo Gallery Of Amusingly Defaced Fire HydrantsFrom wonkiness to silliness: We don't endorse vandalism, of course, but we got some chuckles and even found some inspiration in these pictures of fire hydrant graffiti from around the world. And we'd really would love to stumble across that Super Mario hydrant--or the fire hydrant on fire--in real life...